My pop bottle counter pressure filler / dispenser is a near-clone of C.D. Pritchard’s Pop Bottle Mini Keg Dispenser. Ever since switching to kegging I’ve brought my beer to gatherings by the way of a BierMuncher Bottle Filler into 2L pop bottles, but with “heady” beers I’ll make a mess at that critical moment when removing the wand and getting the cap on.
I wanted a method that would let me fill a bottle under more controlled circumstances, and that led me to Pritchard’s design. The only appreciable difference is that I put a valve and flare fitting on the top of mine so that I could both fill and dispense via the device.
Here’s an overall view of the assembly. In the photo it’s fitted onto a 500mL bottle so it looks a bit ridiculous.
From bottom up here are the parts & descriptions:
- Dip tube: 1/4″ OD soft copper tube
- 1/8″ brass lock nut
- 3/8″ ID, 5/8″ OD rubber grommet
- 1/8″ brass street elbow
- Service valve: Universal Service Valve (#B10-734) from Johnstone Supply
- 1/4″ compression -> 1/4″ MPT fitting
- 1/4″ ball valve
- 1/4″ MPT -> 1/4″ flare fitting
Here’s a closeup of the elbow and service valve. To accommodate the dip tube I drilled a 1/4″ hole up through the bottom of the elbow. I then soldered the top “joint” using lead-free flux & solder.
The underside of the cap showing the locknut and thread tape. When shoved onto the male end of the street fitting the grommet gets expanded a bit so I used a 1/2″ hole punched in the cap instead of 3/8″. The grommet does a great job of sealing the hole, the bottle passed an underwater bubble test holding 25psi.
Here’s what I use to fill the bottle with CO2, a Thumbscrew Core Depressor (#H24-849) also from Johnstone Supply. When purging I’ll go through the top port because it injects gas from the bottom up, and when topping off a filled bottle I’ll use the side port. This is tee’d off of my CO2 regulator.
Not pictured is a beer line “jumper” which is a piece of 3/16″ beverage tube with 1/4″ flare swivel nuts on each end. One end is attached to a liquid-out disconnect while the other is attached to the tap cap.
The first thing I do is to purge the bottle with CO2. I’ll tightly screw on the cap and attache the gas line to the top port and open the main valve. Then by tweaking the side port valve I’ll let a few seconds worth of gas escape, and then close the valve and detach the gas line.
Next the beer line is attached and the valve opened. A small amount of beer will flow into the bottle and then stop because the pressure between the keg & bottle has equalized. By pushing in the side valve pressure in the bottle is lowered and the beer will slowly fill the bottle. It will foam up somewhat because it’s being agitated and warmed, but not to a great extent. When a bit of of foam escapes the side valve I’ll let the side valve close, and the finish the process by closing the top valve and disconnecting everything. For good measure I’ll then apply a shot of 20psi gas to the side port.
The 1/4″ flare threads on the side port let me attach this to any CO2 tank including one of those keg chargers. The same 1/4″ flare fitting on the top lets me attach a picnic tap thus making the pop bottle into a mini keg. However this is a lot of fuss and I predict that in most circumstances I’ll simply take the tap cap off the bottle and pour.
I dislike the large ball valve on top, something rated to 150psi certainly isn’t needed for this project. A small plastic valve would best. An alternative to the valve would be to use a ball lock fitting. Its integrated check valve would perfectly replace the manual ball valve, but would require me to use a ball quick disconnect on the gas line for purging purposes, which would then require a second ball post on the gas in port. A ball post plus flare adapter runs about $20, so another $40 on a tool used to put beer in a pop bottle isn’t worth it.